The present invention relates to a transmission gear especially for a wire guide of a winding machine which is provided with a carriage member which reciprocates on a straight line path. The transmission gear is driven continuously by a shaft rotating in a given direction, which shaft has mounted thereon electro-magnetically actuated clutch members each of which is provided with means for transmitting the rotary power from the drive shaft to the reciprocating carriage member so that the carriage member will be movable in opposite directions along its path depending on which of the clutches is actuated.
Known transmission gears in this field which are used on machines for winding wire into coils have generally employed a driving member in the form of a shaft on which is mounted a pulley or wheel for a first belt together with a second belt and pulley mounted on the same shaft at a distance from the first mentioned pulley. A carriage for the wire guide member is usually mounted to be reciprocated along a given path or track by means of one or the other of the belts. In the past, it has been the practice to mount a pair of magnetic clutches on the carriage itself each clutch of which is connected or associated with one of the drive belts. These clutches, when actuated, would clamp the desired belt to effect movement of the carriage along its track. Conventionally, the distance travelled is dependent upon the period of actuation of a selected magnetic clamp and was usually determined by the positioning of terminal switches in the path of travel of the carriage. Of course the carriage included the wire guide member which moved back and forth with the carriage at a speed corresponding to the speed of rotation of the pulleys and associated belts.
This known arrangement has typically required a relatively large and heavy carriage member to be employed since the magnetic clamping members were mounted directly on the carriage. Also, considerable space is taken up by the drive pulleys themselves and the use of pulleys has limited the number and types of machines with which the transmission gear can be employed since correspondence between the drive pulleys and the associated clamping devices on the carriage is required.
The present invention has for its object the provision of an improved transmission gear where the foregoing disadvantages are avoided. Specifically, the transmission gear of the present invention employs two magnetic clutches mounted on a drive shaft where the output gears of the clutches are idly mounted, i.e., freely rotatable when the associated clutch member is not actuated. Toothed racks are employed to transmit the rotary power from each of the magnetic clutches to the movable carriage member. As will be apparent from the following description, the arrangement of the transmission gear of the present invention results in a substantially more compact transmission gear as well as one that is more stable and able to absorb lateral stresses which may develop during the transmission of power to the carriage. Also, the carriage itself can be made lighter and smaller which is itself a desirable end since the operating life of the apparatus will thus be extended.
The foregoing and other advantages of the present invention will become apparent in the description which follows when considered in connection with the accompanying drawings, in which: